A black civil rights activist has become the unlikely new leader of a white supremacist group – and says he intends to destroy it from within.

James Hart Stern, 54, has been named the director and president of the National Socialist Movement (NSM), in a move which has drawn comparisons to the Spike Lee movie BlacKkKlansman.

The Oscar-winning film tells the true story of a black police officer who infiltrates a branch of the Ku Klux Klan.

Court papers have revealed Stern will use his new position within the NSM to sabotage the Detroit-based group’s defence against an ongoing lawsuit.

The NSM is one of a number of extremist groups being sued over violence at a far-right rally in Charlottesville, during which counter-protester Heather Heyer was killed.

Stern replaced Jeff Schoep as the group’s leader in January, but no details have been released explaining how he got the position.

Image:Tributes were paid to Heather Heyer after her death at the Charlottesville rally

In 2017, Stern posted a video online saying he would be meeting with Schoep to “sign a proclamation acknowledging the NSM denouncing being a white supremacist group”.

He said: “I have personally targeted eradicating the (Ku Klux Klan) and the National Socialist Movement, which are two organisations here in this country which have all too long been given privileges they don’t deserve.”

The activist previously claimed he had duped former Ku Klux Klan leader Edgar Ray Killen – who was convicted of killing three civil rights workers – into handing him power of attorney and ownership of 40 acres of land.

A lawyer later threw out the land transfer and certified that Killen and his family owned the property.

Matthew Heimbach, a white nationalist figure who is attached to the NSM, said members had disagreed with former leader Schoep over the NSM’s direction and resisted ideological changes.

He said some members “essentially want it to remain a politically impotent white supremacist gang”.

Heimbach admitted Stern’s appointment would probably spell the end of the group in its current form.

Image:Members of the NSM previously attended rallies in full Nazi uniform

Members used to attend rallies in full Nazi uniforms, but Schoep recently tried to rebrand the NSM by getting rid of overt displays of Nazi symbols.

The former leader took control of the group in 1994 at the age of 21, according to the Southern Poverty Law Centre.

The organisation is estimated to have about 40 active members, but has drawn larger crowds at rallies.

Lawyers for those suing over the Charlottesville violence have asked the court to sanction Schoep, claiming he failed to turn over documents and access to his social media accounts.

A judge ruled last week that Stern cannot represent the NSM in the case as he does not appear to be a licenced attorney, but the activist did not seem to be deterred.

“It is the decision of the National Socialist Movement to plead liable to all causes of actions listed in the complaint against it,” he wrote.